Hairspring-adjustment retainer



Sept. 4, 1928.

R. E. AMIDON HAIRSPRING ADJUSTMENT RETAINER Filed March 1, 1926 Patented Sept. 4, 1928.

UNETED STATES 1,683,009 PATENT OFFICEQ.

BAY E. AMIDON, OF FLINT, MICHIGAN, ASSIGNOB TO A C SPARK PLUG COMPANY, OF

FLINT, MICHIGAN, A CGMPANY OF MICHIGAN. v

HAIRSPRING-ADJUSTMENT RETAINER.

Application filed March 1, 1926. Serial No. 91,534.

This invention relates to speedometers, and similar instruments. In such instruments there is commonly employed a delicately mounted speed cup carried by a spindle having upper and lower hearings in fixed parts of the instrument. The movements of the speed cup are usually influenced by a rotor element mounted for rotation between the poles of a magnet. Reverse rotation of the speed cup is controlled by a hair spring.

It is an object of this invention to provide improved means for holding the adjusting mechanism for the hair spring. A furtherobject is to provide improved means for limiting the axial movement of the speed cup spindle.

It will be obvious that the invention may be used elsewhere than with the magnetic speedometer for which it is primarily designed.

The following description and the accompanying drawing will give a full understanding of the invention.

Figure 1 is a top plan view of the frame and speed cup of a magneticspeedometer wtih my invention applied. Figure 2 is a sectional view on line 22 of Figure 1.

Referring by reference characters to the drawing numeral 1 represents a frame member which is constructed to carry the various parts of a speedometer and its associated odometer. It will be understood that this frame member is enclosed in a suitable easing having a dial on its front face. The frame member has a depending part 2 within which and within an overhead part are aligned shouldered bearing openings 3 and 4. \Vithin the upper bearing opening +1 is shown the upper jewel carrier 5 and a bearing 6. Within the lower bearing opening are shown the lower jewel carrier 7 mounting a hole jewel 7 and a thrust bearing 8. These jewel carriers and bearing members furnish a pivotal connection for a spindle 9. Secured to the spindle by convenient means as 10 is a speed cup 11. It will be understood that this speed cup is rotatable under the influence of a rotor and magnet, and that the speed cup is provided with suitable designating characters. These. features of the speedometer constitute no part of the invention and are therefore not illustrated.

Rotatably mounted for pivotal action with in the upper bearing opening is a lever mem ber 12. It will be seen that at the pivot, the lever is. provided with an apertured depressed portion 13 which engages the walls of the bearing opening and rests upon the upper-portion of the jewel carrier 1.- At its outer end this lever, has adepending portion to which is connected the outer end of a hair spring 15. The inner end of the hair spring is secured in any convenient Way to the spindle 9. i

For the purpose of retaining the spindle 9 from excessive axial movements there isemployed a resilient member 16. This mem ber 16 has an upper arm 1? overlying the end of the spindle 9. Connecting this upper arm with the frame member is a screw 18, the head of which engages an apertnred depression in the member 16. The member 16 is of U shape, a notch in the bend of the U engaging a rib 22 on the frame member as shown in Figure 2, to prevent rotation of '16 around the screw 18. The lower leg of the resilient member 16 is forked. The forked portion straddles the fastening means 18 and its ends engage the lever member 12 on each side of its pivot.

By the provision of this resilient member 16 and its adjusting screw 18 I am enabled to provide a variable clearance at the end of the spindle 9, and at the same time make use of the resilient pressure of the spring to hold the lever 12 in its bearing and also in any selected position of adjustment.

I claim:

1. A rotary spindle, means for biasing the spindle to rotation in one direction, movable adjusting means for controlling the said biasing means, yielding means to retain the spindle against axial movement and to hold the adjusting means in its position of adj ustinent.

2. A combination set forth in claim 1 wherein the mechanism is in the form of a' substantially U shaped resilient member, one arm positioned over the spindle, the other engaging the adjusting means.

3. A frame having a bearing opening therein, a spindle, a bearing for the spindle in said opening, a biasing spring connected to said spindle, an adjusting member pivoted in said bearing opening and engaging the other end of the spring, a U shaped resilient means one arm positioned over the spindle, its other arm engaging the adjusting means to hold it in the bearing opening and in any selected position of adjustment, means for adjustably securing the U shaped means to the frame.

for said spring, resilient means positioned in adjustably spaced relation to the endofthe a spindle and having a portion engaging theadjusting means to hold it in any positlon of adjustment. 7

5. Means' for limiting the axial movement of a spring controlled spindle and for bolding its spring adjusting means in position for ad ustment, comprising a U shaped resilient membenits upper arm overlying its "spindle, its lowerarm engaging the adjusting means, means i to, vary the tension of the resilient means to adjust theolearance at the end of the spindleand the pressure upon the adfasting means. a V

6,- A frame, a bearing opening-therein, a spindle mounted for rotation in said hearing opening, a lever pivoted in said bearin open ing, resilient means for retainin sai spin- 1 dle lfrom axial movement and or holding the spindle and. being held by securing means to said frame, its lower am: being forked to straddle the, securing means and to engage the lever on the sides of its pivot, adjustment 'ofthe sacnrin'gmeans varying the clearance at the end of the thelever;

7. In a measurin instrument, a speed cup, a indle therefor, rings for said spindle, a i asing spring secured to said spindle,

spindle and pressure upon spring adjusting means rotatable coaxially with said spindle adjacent one of. said bearings, said adjusting" means connected to said spring, yielding means positioned adjacent one end of said spindle to limit axial movement ofsaid spindle, said yielding means en gaging" said ad rnsting means toretain it in an position of adjustment; V

- n testimony whereof I affix my signature." i V *RAY AMI DON. 

